Process for coloring organic products



Patented Apr. 3, 1934 UNITED STATES PATENT OFFICE raocnss Foa COLORING ORGANIC Paoboors No Drawing. Application October 31, 1931, Serial No. 572,431. In Germany November 3, 1930 Claims.

My present invention relates to a process for dyeing organic products and more particularly to such a process in which organic dyes are used as a coloring matter which generally are not soluble in the products to be dyed.

I have found that the phosphatides of the kind of lecithins have a surprisingly good capacity for dissolving numerous dyes which are insoluble or insufllciently soluble in organic substances, such as hydrocarbons and the halogen substitution products thereof, alcohols, ketones, esters, higher fatty acids, fats, oils, resins, waxes, cellulose derivatives and similar substances and that the dye solutions thus obtainable may be used for homogeneously dyeing any organic substance which is miscible with the dye preparationmade with, for instance, lecithin.

My new dyeing method'has some essential advantages when compared with'the prior art.

Thus, the use of lecithin unobjectionably allows the dyeing of foods and any substances used to heighten the enjoyment of food, of products used in pharmacy, of cosmetics and other products which dare not be dyed with the aid of other well known assistants, such as, for instance, oil soluble soaps, organic amines or. soap-like compounds of the latter, such as, for instance, triethanolamine oleate.

Furthermore, I have found that the liquids or pastes as, for instance, oils or oily solutions dyed according to my invention show much less tendency to separate fast products even in' the presence of large proportions of water, such separations easily occurring when preparing the dye solution in oil with the aid of, for instance, triethanolamine oleate. Thus, it becomes possible to prepare solution, for instance, stock solution containing a high amount of the dye. -My new dyeing method is applicable for dyeing substances 40 of different kind. From among the large number of organic compounds and the products obtainable therefrom, to which the new dyeing and coloring process may be applied, may be named, without in any way limiting the invention thereto, hydrocarbons, alcohols, ethers, aldehydes, ketones, carboxylic acids, esters, nitro-compounds and amino compounds of the aliphatic. aromatic,

hydroaromatic and heterocyclic series, natural and artificial resins, waxes, fats, fatty acids, cellulose derivatives and threads, bands, films or plastic masses made therefrom; varnishes from cellulose estersand ethers, fatty varnishes, spirit varnishes, and the like; oil emulsions as used, for instance, in the leather industry; candles, soaps,

polishing waxes, shoe polishes, printing colors; cosmetics and galenic preparations. a

When carrying out my dyeing method, it is a matter of indifference whether the dye is dissolved first in the cold or, if necessary, in the warm lecithin and then this dye solution is added to the substance to be dyed, or whether the phosphatide is first incorporated into the goods to be dyed and then followed by treatment with the coloring matter.

In the case of mordant dyes which are soluble either in the lacithin or in the mixture containing the phosphatide, the formation of the lake with, v

for instance, heavy metal salts of fatty acids or naphthenic acids may be carried out either during or after the dissolution of the dye. The addition of the compound forming the lake, can be made at any desired stage of the operation. Thus, it may be advisable, for instance, to form the dye lake in the product,-. for instance, a film, already dyed according to my invention, by aftertreating it with a lake-forming substance.

The solubility and the brightness of the coloration may be improved in some cases, especially when using mordant' dyes of the alizarine series, by addition of an oil-soluble amine such as, for instance, triethanolaminemonooleate, dibenzylamine and so on. In the case of certain dyes as, for instance, mordant dyes of the alizarine series, the solubility 'is only attained by the combination of the phosphatide and the oil-soluble base.

The degree of purity of the phosphatide used as a solvent assistant such as, for instance, lecithin obtained from soy beans is in the most cases not of importance. Generally it is suillcient to use the second quality of products obtained when preparing the phosphatides from the raw materials. The products known on the market as textile lecithin, are very suitable for the proces in question. Impurities contained in the lecithin and remaining undissolved maybe easily removed by filtration.

My invention is illustrated in the examples following hereafter, the parts being by weight:-

Example 1.-1 part of Kiton Fast Yellow 3 G (Schultz, Farbstofitabellen, 7th,edition, No. 748) is dissolved in 9 parts of textile lecithin while stirring the mixture warmed on the water bath. The solution obtained may be mixed with 390 parts of an oil varnish, whereby a clear transparent solution is obtained.

Example 2.-1 part of Patent Blue V (Schultz, Farbstoiftabellen, 7th edition, No. 826? is dissolved as prescribed in Example 1 in 9 parts of textile lecithin. The deep bluish green mass thus obtained, may be used for dyeing a composition for candles consisting, for instance, of 60 parts-of stearic acid and 40 parts of ceresin. There is thus obtained an intensely greenish-blue candle wax; the wax colored under like conditions with triethanolamine is darker, more glazed and duller. Example 3.--'0.5 part-of Acid Red XB (Schultz, Farbstoiftabellen, 7th edition, No. 863) is heated to 90 C. together with 10 parts of lecithin until dissolved. The dye preparation may be applied for coloring an oil emulsion used for the treatment of leather. 7

Example 4.-1 part of Alizarine Viridin FF (powder) (Schultz, Farbstofftabellen, 7th edition, No. 1193) is dissolved in 15 parts of textile lecithin and the solution is mixed with a wax composition. By addition of a lake-forming compound, thus as, for instance, chromium naphthenate, the coloration may be brightened.

Example 5.-- 1 part of Alizarine' Marron W (powder) (Schultz, Farbstofftabellen, 7th edition, No. 1159) is stirred on the water bath with 9 parts of textile lecithin until dissolved. The preparation may be used for coloring an oil varnish diluted with toluene. The intensity of the coloration may be increased by addition of aluminium oleate or chrome naphthenate.

Example 6.L part of Fanal Green LB (2. complex salt of a basic dye) Schultz, Farbstoiftabellen, 7th edition, No. 765) is dissolved while being warmed in 15 parts of lecithin. The intensely yellowish green colored dye preparation may be used for coloring a cellulose other varnish (containing, for instance, an aromatic hydrocarbon and an alcohol as solvents).

Example 7. -In a meltcontaining' 60 parts of stearic acid and 5 parts of lecithin there are dissolved on the water bath 0.2 part of the azo dye obtained by diazotizing 3.5-dichloro-2-amino-lhydroxybenzene and coupling with 1-phenyl-3- methyl-5-pyrazolone. The greenish yellow mass becomes reddish yellow on addition of aluminium chloride.

Example 8.0.5' part of AlizarineRG (Schultz, Farbstoiftabellen, 7th edition, No. 1154) and 10 parts of triethanolamino-mono-oleate are dissolved in 10 parts of textile lecithin. The dye solution may be added, for instance, to a cellulose laurate varnish dissolved in toluene. On addition of an aluminium-, copper-, ironor nickel salt, the shade of the color may be varied in known manner.

Example 9.--Dyes which are insoluble in oils,

such as linseed oil or paraifine oil, (for instance those mentioned in Examples 2:, 4 and 6) are dissolved in the manner described in lecithin. With the aid of the dye preparations thus obtainable, fatty acid esters, such as linseed oil, or'benzine hydrocarbons, such as parafline oil, may be homogeneously dyed without separation of the coloring matter.

In each case,'a clear and homogeneous solution of the dyes is obtainable in the products to be dyed and no separation of the coloring matter occurs even when storing them for a long time.

My invention is not limited to the foregoing examples or to the specific details given therein. Thus, I may use, for instance, a lecithin of another origin. Furthermore, dyes of the different groups may be used and generally I may apply as a coloring matter water-soluble salts of basic dyes, dye acids and .salts thereof, numerous difficulty soluble organic pigments, aminoanthraquinones and aminohydroxyanthraquinones, acid mordant dyes especially in form of the dye lakes, furthermore, complex compounds of basic dyes with heteropoly acids, such as phosphotungstic acid, or vat dyes.

A few simple comparative experiments should be made. to determine the best kind of dye and the most suitable amount of the phosphatideto employ with a particular product to be dyed.

What I claim is:

1. A process for dyeing liquid or fusible organic products with coloring substances which are insoluble or difficulty soluble in the products to be dyed which comprises adding a lecithin as a solvent assistant.

2. A process for dyeing fatty organic substances of the group consisting of fats, oils, fatty acids,

waxes and hydrocarbons of the parafline series with organic dyes which are'insoluble' or difficulty'soluble in the products to be dyed, which comprises adding a lec'thin as a solvent assistant.

3. A process for dyeing fatty organic substances of the group consistng of fats, oils, fatty acids, waxes and hydrocarbons of the parafiine series with a salt of a basic dye which is insoluble or difficulty soluble in the products to be dyed, which comprises adding alecithin as a solvent assistant.

, 4. A process for dyeing fatty organic substances of the group consisting of fats, oils, fatty acids, waxes and hydrocarbons of the paraffine series with an acid azo dye which is insoluble or difficulty soluble in the products to be dyed, which comprises adding a lecithin as a solvent assistant.

5. A process for dyeing fatty organic substances of the group consisting of fats, oils. fatty acids, waxes and hydrocarbons of the parafiine series with a mordant' dye which is insoluble or difficulty soluble in the products to be dyed, which comprises adding a lecithin as a solvent assistant.

6. A composition of matter comprising a liquidor fusible organic substance and dissolved therein a lecithin and an organic dye originally insoluble or difficulty soluble in said organic substance.

'7. A composition of matter comprising a fatty organic substance of the group consisting of fats, oil-s, fatty acids, waxes and hydrocarbons of the parafilne series and dissolved therein a lecithin and an organ'c dye originally insoluble or diificulty soluble in said fatty substance.

8. A composition of matter comprising a fatty organic substance of the group consisting of fats, oils, fatty acids, waxes and hydrocarbons of the parafline series and dissolved therein a lecithin and a salt of a basic dye orig'nally insoluble or difiiculty soluble in said fatty substance.

9. A composition of matter comprising a fatty organic substance of the group consisting of fats,

oils, fatty acids, waxes and hydrocarbons of the par-affine series and dissolved therein alecith'n and an acid azo dye originally insoluble or difficulty soluble in said fatty substance.

10. A'composition of matter comprising a fatty organic substance of the group consisting of fats, o Is, fatty acids, waxes and hydrocarbons of the parafiine series and dissolved therein a lecithin and a mordantdye originally insoluble or difli culty soluble in said fatty substance.

' PAUL SCHLACK. 

